chore(deps): SvelteKit 3 with adapter-static 4 and TypeScript 6, full-tree npm audit (#5021)

Merges Renovate's kit 3 (PR #149) and adapter-static 4 (PR #148) bumps,
plus the migration they need. The mechanical part is `sv migrate
sveltekit-3`, run one task at a time and reviewed:

- svelte.config.js is gone. Its options move into sveltekit() in
  vite.config.ts, exported as kitOptions so vitest.config.ts runs the
  same kit setup, including the $test-utils alias the tests import.
- $lib becomes #lib through package.json "imports". There is no
  src/lib/index, so only the "#lib/*" entry is kept.
- tsconfig extends $app/tsconfig.
- Peer floors raised to kit 3's requirements: svelte ^5.57.1, vite
  ^8.0.12, svelte-check ^4.7.5.

By hand, from the codemod's list of non-automated tasks:

- goto's replaceState option is now replace; keepFocus becomes
  reset: false. For the search typeahead, reset: false also stops the
  scroll-to-top, which is wanted while typing.
- The test setup mocks drop pushState/replaceState and $app/paths
  base/assets, which kit 3 removed, and mock refreshAll in place of
  invalidateAll.
- The other flagged files only read page.url or goto internal routes,
  so they needed no change.

TypeScript goes to ^6, not the ^7 Renovate offers: kit 3 declares
typescript ^6 as a peer and svelte-check 4.7 accepts ^5 || ^6. Move to
7 once both accept it.

With Tailwind 4 and kit 3 in, `npm audit` on the whole tree reports 0,
so the web lane now audits every dependency rather than only what
ships to browsers.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/lib/components/SuggestionFeed.test.ts

@@ -8,19 +8,19 @@ vi.mock('@tanstack/svelte-query', async (orig) => {
   return { ...actual, useQueryClient: () => ({ invalidateQueries: invalidateMock }) };
 });
 
-vi.mock('$lib/api/suggestions', () => ({
+vi.mock('#lib/api/suggestions.js', () => ({
   createSuggestionsQuery: vi.fn(),
   createSnoozesQuery: vi.fn(),
   snoozeSuggestion: vi.fn().mockResolvedValue(undefined),
   unsnoozeSuggestion: vi.fn().mockResolvedValue(undefined)
 }));
 
-vi.mock('$lib/api/requests', () => ({
+vi.mock('#lib/api/requests.js', () => ({
   createRequest: vi.fn().mockResolvedValue({})
 }));
 
 const pushToastMock = vi.fn();
-vi.mock('$lib/stores/toast.svelte', () => ({
+vi.mock('#lib/stores/toast.svelte.js', () => ({
   pushToast: (...args: unknown[]) => pushToastMock(...args)
 }));
 
@@ -30,9 +30,9 @@ import {
   createSnoozesQuery,
   snoozeSuggestion,
   unsnoozeSuggestion
-} from '$lib/api/suggestions';
-import { createRequest } from '$lib/api/requests';
-import type { ArtistSuggestion, SuggestionSnooze } from '$lib/api/types';
+} from '#lib/api/suggestions.js';
+import { createRequest } from '#lib/api/requests.js';
+import type { ArtistSuggestion, SuggestionSnooze } from '#lib/api/types.js';
 
 const oneSeed: ArtistSuggestion = {
   mbid: 'mb1',